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1.
Learn Individ Differ ; 1092024 Jan.
Article in English | MEDLINE | ID: mdl-38962323

ABSTRACT

Math and reading skills are known to be related, and predictors of each are well researched. What is less understood is the extent to which these predictors, uniquely and collectively, overlap with one another, are differentially important for different academic skills, and account for the overlap of math and reading. We examined 20 potential predictors from four domains (working memory, processing speed, attention, and language) using latent variables and both timed and untimed achievement skill, in a sample (N=212) of at-risk middle schoolers, half of whom were English learners. The predictors accounted for about half of the overlap among achievement skills, suggesting that other factors (e.g., domain specific skills) might also be relevant for the overlap. We also found some differential prediction (language for reading, working memory for math). The present results extend and refine our understanding of the contribution of these cognitive predictors for reading and math.

2.
Clin Neuropsychol ; : 1-26, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38453891

ABSTRACT

Objective: Doctoral education is a cornerstone in the training of clinical neuropsychologists. However, we know little about perceptions, practices, and needs of the faculty who oversee doctoral training in clinical neuropsychology (CN). Method: Seventy-one faculty from 45 doctoral programs providing CN training completed at least part of a survey assessing characteristics of their programs, current training practices and views, and challenges to CN doctoral training. Results: Over half of CN faculty reported having zero or only one CN colleague. CN faculty reported that the goals of CN doctoral training are research training, clinical training, and acquisition of knowledge and skills reflected in the Houston Conference Guidelines (HCG). CN faculty reported that doctoral trainees obtain more clinical hours than faculty would like and endorsed alternative clinical metrics, including competency-based ratings. CN faculty are divided about the benefits of a required two-year postdoctoral CN fellowship. Conclusions: The HCG states that specialization in CN begins at the doctoral level. CN faculty in doctoral programs are fully immersed in the early development and education of future CN researchers and practitioners. Tensions between clinical and research training in CN at the doctoral level-and student overemphasis on accruing clinical hours-might place CN at risk for failing to make research innovations necessary for our field to evolve and thrive. More CN doctoral faculty are needed to serve as mentors to students, especially for students from backgrounds that have been historically excluded and marginalized. A greater voice from CN doctoral faculty in CN governance is needed.

3.
JCI Insight ; 7(23)2022 12 08.
Article in English | MEDLINE | ID: mdl-36227697

ABSTRACT

Preeclampsia is a serious pregnancy disorder that lacks effective treatments other than delivery. Improper sensing of oxygen changes during placentation by prolyl hydroxylases (PHDs), specifically PHD2, causes placental hypoxia-inducible factor-1 (HIF1) buildup and abnormal downstream signaling in early-onset preeclampsia, yet therapeutic targeting of HIF1 has never been attempted. Here we generated a conditional (placenta-specific) knockout of Phd2 in mice (Phd2-/- cKO) to reproduce HIF1 excess and to assess anti-HIF therapy. Conditional deletion of Phd2 in the junctional zone during pregnancy increased placental HIF1 content, resulting in abnormal placentation, impaired remodeling of the uterine spiral arteries, and fetal growth restriction. Pregnant dams developed new-onset hypertension at midgestation (E9.5) in addition to proteinuria and renal and cardiac pathology, hallmarks of severe preeclampsia in humans. Daily injection of acriflavine, a small molecule inhibitor of HIF1, to pregnant Phd2-/- cKO mice from E7.5 (prior to hypertension) or E10.5 (after hypertension had been established) to E14.5 corrected placental dysmorphologies and improved fetal growth. Moreover, it reduced maternal blood pressure and reverted renal and myocardial pathology. Thus, therapeutic targeting of the HIF pathway may improve placental development and function, as well as maternal and fetal health, in preeclampsia.


Subject(s)
Hypertension , Prolyl Hydroxylases , Pregnancy , Humans , Female , Mice , Animals , Acriflavine , Hypoxia-Inducible Factor 1 , Placenta , Hypertension/drug therapy
4.
Cell Death Dis ; 13(2): 191, 2022 02 26.
Article in English | MEDLINE | ID: mdl-35220394

ABSTRACT

Dynamic changes in physiologic oxygen are required for proper placenta development; yet, when low-oxygen levels persist, placental development is halted, culminating in preeclampsia (PE), a serious complication of pregnancy. Considering mitochondria's function is intimately linked to oxygen changes, we investigated the impact of oxygen on mitochondrial dynamics in placental mesenchymal stromal cells (pMSCs) that are vital for proper placental development. Transmission electron microscopy, proximity ligation assays for mitochondrial VDAC1 and endoplasmic reticulum IP3R, and immunoanalyses of p-DRP1 and OPA1, demonstrate that low-oxygen conditions in early 1st trimester and PE promote mitochondrial fission in pMSCs. Increased mitochondrial fission of mesenchymal cells was confirmed in whole PE placental tissue sections. Inhibition of DRP1 oligomerization with MDiVi-1 shows that low oxygen-induced mitochondrial fission is a direct consequence of DRP1 activation, likely via HIF1. Mitophagy, a downstream event prompted by mitochondrial fission, is a prominent outcome in PE, but not 1st trimester pMSCs. We also investigated whether mesenchymal-epithelial interactions affect mitochondrial dynamics of trophoblasts in PE placentae. Exposure of trophoblastic JEG3 cells to exosomes of preeclamptic pMSCs caused heightened mitochondrial fission in the cells via a sphingomyelin-dependent mechanism that was restored by MDiVi-1. Our data uncovered dichotomous regulation of mitochondrial fission and health in human placental mesenchymal cells under physiologic and pathologic hypoxic conditions and its impact on neighboring trophoblast cells.


Subject(s)
Mesenchymal Stem Cells , Pre-Eclampsia , Cell Line, Tumor , Female , Homeostasis , Humans , Hypoxia/metabolism , Mesenchymal Stem Cells/pathology , Mitochondria/pathology , Mitochondrial Dynamics , Oxygen/metabolism , Placenta/metabolism , Pre-Eclampsia/pathology , Pregnancy , Trophoblasts/metabolism
5.
Front Cell Dev Biol ; 9: 652607, 2021.
Article in English | MEDLINE | ID: mdl-34055782

ABSTRACT

The mechanisms contributing to excessive fibronectin in preeclampsia, a pregnancy-related disorder, remain unknown. Herein, we investigated the role of JMJD6, an O2- and Fe2+-dependent enzyme, in mediating placental fibronectin processing and function. MALDI-TOF identified fibronectin as a novel target of JMJD6-mediated lysyl hydroxylation, preceding fibronectin glycosylation, deposition, and degradation. In preeclamptic placentae, fibronectin accumulated primarily in lysosomes of the mesenchyme. Using primary placental mesenchymal cells (pMSCs), we found that fibronectin fibril formation and turnover were markedly impeded in preeclamptic pMSCs, partly due to impaired lysosomal degradation. JMJD6 knockdown in control pMSCs recapitulated the preeclamptic FN phenotype. Importantly, preeclamptic pMSCs had less total and labile Fe2+ and Hinokitiol treatment rescued fibronectin assembly and promoted lysosomal degradation. Time-lapse imaging demonstrated that defective ECM deposition by preeclamptic pMSCs impeded HTR-8/SVneo cell migration, which was rescued upon Hinokitiol exposure. Our findings reveal new Fe2+-dependent mechanisms controlling fibronectin homeostasis/function in the placenta that go awry in preeclampsia.

6.
Front Cell Dev Biol ; 9: 652651, 2021.
Article in English | MEDLINE | ID: mdl-34017832

ABSTRACT

Aberrant ceramide build-up in preeclampsia, a serious disorder of pregnancy, causes exuberant autophagy-mediated trophoblast cell death. The significance of ceramide accumulation for lysosomal biogenesis in preeclampsia is unknown. Here we report that lysosome formation is markedly increased in trophoblast cells of early-onset preeclamptic placentae, in particular in syncytiotrophoblasts. This is accompanied by augmented levels of transcription factor EB (TFEB). In vitro and in vivo experiments demonstrate that ceramide increases TFEB expression and nuclear translocation and induces lysosomal formation and exocytosis. Further, we show that TFEB directly regulates the expression of lysosomal sphingomyelin phosphodiesterase (L-SMPD1) that degrades sphingomyelin to ceramide. In early-onset preeclampsia, ceramide-induced lysosomal exocytosis carries L-SMPD1 to the apical membrane of the syncytial epithelium, resulting in ceramide accumulation in lipid rafts and release of active L-SMPD1 via ceramide-enriched exosomes into the maternal circulation. The SMPD1-containing exosomes promote endothelial activation and impair endothelial tubule formation in vitro. Both exosome-induced processes are attenuated by SMPD1 inhibitors. These findings suggest that ceramide-induced lysosomal biogenesis and exocytosis in preeclamptic placentae contributes to maternal endothelial dysfunction, characteristic of this pathology.

7.
Article in English | MEDLINE | ID: mdl-32144130

ABSTRACT

INTRODUCTION: Gestational diabetes mellitus (GDM), a common pregnancy disorder, increases the risk of fetal overgrowth and later metabolic morbidity in the offspring. The placenta likely mediates these sequelae, but the exact mechanisms remain elusive. Mitochondrial dynamics refers to the joining and division of these organelles, in attempts to maintain cellular homeostasis in stress conditions or alterations in oxygen and fuel availability. These remodeling processes are critical to optimize mitochondrial function, and their disturbances characterize diabetes and obesity. METHODS AND RESULTS: Herein we show that placental mitochondrial dynamics are tilted toward fusion in GDM, as evidenced by transmission electron microscopy and changes in the expression of key mechanochemical enzymes such as OPA1 and active phosphorylated DRP1. In vitro experiments using choriocarcinoma JEG-3 cells demonstrated that increased exposure to insulin, which typifies GDM, promotes mitochondrial fusion. As placental ceramide induces mitochondrial fission in pre-eclampsia, we also examined ceramide content in GDM and control placentae and observed a reduction in placental ceramide enrichment in GDM, likely due to an insulin-dependent increase in ceramide-degrading ASAH1 expression. CONCLUSIONS: Placental mitochondrial fusion is enhanced in GDM, possibly as a compensatory response to maternal and fetal metabolic derangements. Alterations in placental insulin exposure and sphingolipid metabolism are among potential contributing factors. Overall, our results suggest that GDM has profound impacts on placental mitochondrial dynamics and metabolism, with plausible implications for the short-term and long-term health of the offspring.


Subject(s)
Diabetes, Gestational/physiopathology , Mitochondrial Dynamics , Placenta/physiopathology , Cell Line , Ceramides/metabolism , Diabetes, Gestational/metabolism , Female , Homeostasis , Humans , Insulin/administration & dosage , Insulin/metabolism , Mitochondria/metabolism , Mitochondria/physiology , Mitochondria/ultrastructure , Mitochondrial Proteins/metabolism , Placenta/metabolism , Placenta/ultrastructure , Pregnancy
8.
JCI Insight ; 4(8)2019 04 18.
Article in English | MEDLINE | ID: mdl-30996134

ABSTRACT

Human placenta development and a successful pregnancy is incumbent upon precise oxygen-dependent control of trophoblast migration/invasion. Persistent low oxygen leading to failed trophoblast invasion promotes inadequate spiral artery remodeling, a characteristic of preeclampsia. Angiomotin (AMOT) is a multifaceted scaffolding protein involved in cell polarity and migration, yet its upstream regulation and significance in the human placenta remain unknown. Herein, we show that AMOT is primarily expressed in migratory extravillous trophoblast cells (EVTs) of the intermediate and distal anchoring column. Its expression increases after 10 weeks of gestation when oxygen tension rises and EVT migration/invasion peaks. Time-lapse imaging confirmed that the AMOT 80-kDa isoform promotes migration of trophoblastic JEG3 and HTR-8/SVneo cells. In preeclampsia, however, AMOT expression is decreased and its localization to migratory fetomaternal interface EVTs is disrupted. We demonstrate that Jumonji C domain-containing protein 6 (JMJD6), an oxygen sensor, positively regulates AMOT via oxygen-dependent lysyl hydroxylation. Furthermore, in vitro and ex vivo studies show that transforming growth factor-ß (TGF-ß) regulates AMOT expression, its interaction with polarity protein PAR6, and its subcellular redistribution from tight junctions to cytoskeleton. Our data reveal an oxygen- and TGF-ß-driven migratory function for AMOT in the human placenta, and implicate its deficiency in impaired trophoblast migration that plagues preeclampsia.


Subject(s)
Intercellular Signaling Peptides and Proteins/metabolism , Microfilament Proteins/metabolism , Oxygen/metabolism , Pre-Eclampsia/pathology , Trophoblasts/pathology , Angiomotins , Cell Line, Tumor , Cell Movement , Disease Susceptibility , Female , Gestational Age , Humans , Infant, Newborn , Intravital Microscopy , Jumonji Domain-Containing Histone Demethylases/metabolism , Male , Placentation , Pregnancy , Pregnancy Trimester, First , Protein Isoforms/metabolism , Time-Lapse Imaging , Trophoblasts/metabolism
9.
Cell Death Dis ; 9(3): 298, 2018 02 20.
Article in English | MEDLINE | ID: mdl-29463805

ABSTRACT

Mitochondria are in a constant balance of fusing and dividing in response to cellular cues. Fusion creates healthy mitochondria, whereas fission results in removal of non-functional organelles. Changes in mitochondrial dynamics typify several human diseases. However, the contribution of mitochondrial dynamics to preeclampsia, a hypertensive disorder of pregnancy characterized by placental cell autophagy and death, remains unknown. Herein, we show that the mitochondrial dynamic balance in preeclamptic placentae is tilted toward fission (increased DRP1 expression/activation and decreased OPA1 expression). Increased phosphorylation of DRP1 (p-DRP1) in mitochondrial isolates from preeclamptic placentae and transmission electron microscopy corroborated augmented mitochondrial fragmentation in cytotrophoblast cells of PE placentae. Increased fission was accompanied by build-up of ceramides (CERs) in mitochondria from preeclamptic placentae relative to controls. Treatment of human choriocarcinoma JEG3 cells and primary isolated cytrophoblast cells with CER 16:0 enhanced mitochondrial fission. Loss- and gain-of-function experiments showed that Bcl-2 member BOK, whose expression is increased by CER, positively regulated p-DRP1/DRP1 and MFN2 expression, and localized mitochondrial fission events to the ER/MAM compartments. We also identified that the BH3 and transmembrane domains of BOK were vital for BOK regulation of fission. Moreover, we found that full-length PTEN-induced putative kinase 1 (PINK1) and Parkin, were elevated in mitochondria from PE placentae, implicating mitophagy as the process that degrades excess mitochondria fragments produced from CER/BOK-induced fission in preeclampsia. In summary, our study uncovered a novel CER/BOK-induced regulation of mitochondrial fission and its functional consequence for heightened trophoblast cell autophagy in preeclampsia.


Subject(s)
Ceramides/metabolism , Mitochondrial Dynamics , Pre-Eclampsia/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Adult , Animals , Autophagy , Ceramides/adverse effects , Dynamins/genetics , Dynamins/metabolism , Female , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Humans , Male , Mice , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitochondria/genetics , Mitochondria/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Phosphorylation , Placenta/metabolism , Pre-Eclampsia/genetics , Pre-Eclampsia/physiopathology , Pregnancy , Protein Domains , Proto-Oncogene Proteins c-bcl-2/chemistry , Proto-Oncogene Proteins c-bcl-2/genetics , Young Adult
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